Many of these find a natural outlet through Seely Creek, the only stream of note in the township, and which empties into the Flat River near Smyrna in Ionia County.

16.0% of all households were made up of individuals, and 4.6% had someone living alone who was 65 years of age or older.

Grattan Township is served by three separate school districts.

The majority of the township is served by Belding Area School District to the east in Ionia County.

A small western portion of the township is served by Rockford Public Schools, and the southern portion of the township is served by Lowell Area Schools.